Mamiya 645 or Bronica ETRS?

I'm looking for a medium format SLR system to accompany my Bronica RF645 and Mamiya 6 rangefinders and mostly to shoot color transparencies. I'm looking for a rectangular format camera that is reasonable lightweight (6x4.5) and has great lenses.

I have played around recently with a Mamiya 645 Pro. The lenses were great. I wasn't too crazy about its "plasticy' feel though, and also didn't like the fact that you had to use a cheesy little adapter just to use a standard cable release.

I also prefer leaf shutter lenses as opposed to focal plane shutters in cameras. Leaf shutters are so nice and quiet and seem to me to fail less than focal plane shutters. So this made me look to the Bronica ETRS. I used to own a Bronica SQ-A and I know that that camera had a more solid feel to it. So I assume the ETRS is the same. The ETRS also has a cable release socket and a great selection of lenses, though more expensive than the Mamiya's lenses.

I was just looking for opinions from folks who have used one or both cameras and what their opinions are. Thanks!

Get an ETRSi instead of an ETRS. The ETRSi has bulb and MLU and is newer. As for the rest I don't think there is much difference in the 2 brands except for the feel. Bronica Lenses are great and not utterly expensive secondhand. But don't forget, while the leafshutter is indeed very silent the sound of the mirror going up isn't. I never had an issue with the sound as I never use it in a situation that it has to be silent. i can imagine that if you do things like ceremonies and stuff it might be different.

My Mamiya 645 AFD is much quieter than the Bronica SQAi that we have and much lighter and easier to handle. Lenses are more expensive than Bronica lenses but seem to be sharper to me. I like the fact the motor drive is built in and the camera runs on AA batteries.

I like the fact the ETRSI motordrive isn't built in -) If you've ever had a motor fail you'll like being able to switch to the crank. The beauty of the ETRSI is you can build what you want. A basic WLF and crank setup. Or a full hog metering TTL prism and motor setup. I have to admit I also like AA batteries but the Bronica winders all use AA.

I can only comment on the Mamiya, because that's all I've used.

I finally got around to buying a 645 Pro for a trip to Nepal a couple of weeks ago and I'm absolutely chuffed with it. You're right about it being pretty plasticy, but it is a pretty strong, dense plastic. I have total faith it will hold up to my hiking uses both here and overseas. The lenses are brilliant and really great prices these day too. As far as noise goes, the mirror seems to be just as loud as the focal plane shutter, so unless you shoot with the mirror locked up often, I'm not sure the Bronica would be all that much more quiet.

If you get a Bronica, I highly recommend the speed grip to go with it. It makes handling a lot easier and faster.

The Bronica lenses are very sharp, and was pointed out, they're not too expensive, especially the MC and EII series. The PE lens tend to go for a higher price.